1. Field of the Invention
The present invention relates to slides for microscopes, and in particular it relates to plastic slides each having a hydrophilic surface and a method for manufacturing them.
2. Description of the Prior Art
A slide for a microscope is used to examine a specimen thereon through the microscope. The microscopic examination is usually carried out as follows: The specimen which will be examined through the microscope is first generally microsectioned, if it is not so thin as to transmit light. Then the specimen is put on the slide, and it is stained, if necessary. A cover is then put thereon, and the specimen is now ready for examination. The term "slide" used in this specification is a general term inclusive of the slide itself and the cover. The slide can be handled in the following either manner: (1) after the microscopic examination, the slide with a specimen is discarded, or (2) after the examination, the slide is preserved as a permanent specimen, which may be prepared by putting a fixed specimen on the slide, staining the specimen, dehydrating it and coating it with a mounting medium, and putting a cover thereon.
The above-mentioned handling (1) is mainly employed in clinical examination That is, in examining urine, sputum, blood, feces and the like, each specimen is put on the slide, and after the microscopic examination, it is thrown away. The other handling (2) is principally taken in the medical science of pathology and the like, and for example, microsectioned tissues of internal organs may be preserved as permanent specimens for a microscope.
Heretofore, the slides for the above-mentioned purposes have been made from glass since the microscope began to be used. However, the slides made of glass, i.e., the glass slides have the following drawbacks: (A) they are liable to be broken; (B) they are heavy (their density is high); (C) they are brittle and weak, so that they cannot take a thin form; (D) they cannot be folded; (E) they cannot be cut arbitrarily; (F) after use, they cannot be burnt away, which fact causes an environmental problem; (G) when stored for a long period of time or under bad conditions (under such high-temperature and high-humidity conditions as in a ship's hold), they deteriorate and become whitely turbid; (H) alkali and heavy metal are separated out from the used glass, and these substances have a bad influence on specimens; (I) a worker is apt to be hurt by their edges or when the glass is broken, and at this time, if the specimen contains a pathogen, for example, a hepatitis virus or an AIDS virus, the worker will be infected therewith through the wound position, in high probability; and (J) they are difficult to cut with a high demensional accuracy in manufacturing them, and after cutting, their surfaces are contaminated with a glass powder and therefore an additional process such as a washing step is required.
In order to partially eliminate these drawbacks, plastic covers have been recently used in some fields. However, these plastic covers are made only by cutting a high-transparent film, for example, a cellulose triacetate film. Therefore, such covers are definitely different from the slides of the present invention, and hence the latter is not restricted by the former at all.